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1.
Reprod Health ; 16(1): 81, 2019 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-31196113

RESUMEN

BACKGROUND: Infertility affects one in seven couples; many of these need in vitro fertilisation (IVF). IVF involves external hormones to stimulate a woman's ovaries to produce eggs which are harvested surgically. Embryos, created in the laboratory by mixing eggs with sperm, are grown in culture for a few days before being replaced within the uterus (fresh embryo transfer). Spare embryos are usually frozen with a view to transfer at a later point in time - especially if the initial fresh transfer does not result in a pregnancy. Despite improvements in technology, IVF success rates remain low with an overall live birth rate of 25-30% per treatment. Additionally, there are concerns about health outcomes for mothers and babies conceived through IVF, particularly after fresh embryo transfer, including maternal ovarian hyperstimulation syndrome (OHSS) and preterm delivery. It is believed that high levels of hormones during ovarian stimulation could create a relatively hostile environment for embryo implantation whilst increasing the risk of OHSS. It has been suggested that freezing all embryos with the intention of thawing and replacing them within the uterus at a later stage (thawed frozen embryo transfer) instead of fresh embryo transfer, may lead to improved pregnancy rates and fewer complications. We aim to compare the clinical and cost effectiveness of fresh and thawed frozen embryo transfer, with the primary aim of identifying any difference in the chance of having a healthy baby. METHODS: E-Freeze is a pragmatic, multicentre two-arm parallel group randomised controlled trial where women aged ≥18 and < 42 years, with at least three good quality embryos are randomly allocated to receive either a fresh or thawed frozen embryo transfer. The primary outcome is a healthy baby, defined as a term, singleton, live birth with appropriate weight for gestation. Cost effectiveness will be calculated from a healthcare and societal perspective. DISCUSSION: E-Freeze will determine the relative benefits of fresh and thawed frozen embryo transfer in terms of improving the chance of having a healthy baby. The results of this pragmatic study have the potential to be directly transferred to clinical practice. TRIAL REGISTRATION: ISRCTN registry: ISRCTN61225414 . Date assigned 29/12/2015.


Asunto(s)
Criopreservación/economía , Transferencia de Embrión/métodos , Fertilización In Vitro/métodos , Congelación , Infertilidad Femenina/terapia , Nacimiento Vivo/epidemiología , Adolescente , Adulto , Análisis Costo-Beneficio , Criopreservación/métodos , Implantación del Embrión , Embrión de Mamíferos , Femenino , Fertilización In Vitro/legislación & jurisprudencia , Humanos , Síndrome de Hiperestimulación Ovárica/epidemiología , Síndrome de Hiperestimulación Ovárica/prevención & control , Inducción de la Ovulación , Embarazo , Complicaciones del Embarazo/epidemiología , Resultado del Embarazo , Índice de Embarazo , Adulto Joven
2.
Ultrasound Med Biol ; 41(11): 2798-805, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26278634

RESUMEN

Our aim in the study described here was to assess the feasibility of spatiotemporal image correlation power Doppler quantification of the endometrium with two techniques: spherical samples and whole tissue. We scanned 51 women in the midluteal phase of the menstrual cycle: STIC assessment of the whole endometrium was not possible in 10% of cases, whereas spherical analysis was possible in all. The time taken for data set analysis was much longer for the whole endometrium compared with spherical analysis (1478.9 ± 291 s vs. 266.8 ± 39.3 s, p < 0.05). Intra-class correlation coefficients for the vascularization flow index (VFI) were similar for both methods. Volumetric vascularity indices were higher when spherical sampling was conducted. Significant cycle-to-cycle variability in the vascularity indices was present, with coefficients of variation exceeding 20% for both techniques. We found that STIC power Doppler quantification of the whole endometrium is possible in the majority of cases, however, it is time consuming and limited by significant cycle-to-cycle variability.


Asunto(s)
Endometrio/irrigación sanguínea , Endometrio/diagnóstico por imagen , Imagenología Tridimensional/métodos , Ultrasonografía Doppler/métodos , Adulto , Estudios de Cohortes , Estudios de Factibilidad , Femenino , Humanos , Estudios Prospectivos , Reproducibilidad de los Resultados , Adulto Joven
3.
Ultrasound Med Biol ; 37(3): 364-75, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21276655

RESUMEN

Three-dimensional power Doppler angiography and 4D View allows quantification of placental "vascularity" using sonobiopsy or manual tracing. We used two vascular "biopsy" techniques: nontargeted sphere placement and systematic uniform random sphere placement (SURS). We hypothesised that random application of spheres would result in less reliability and the basal zone would display higher values than the chorionic zone. Forty women between 18+6 to 21+6 weeks gestation were recruited. A single volume of the placenta was acquired. Data was analysed twice by a single observer. Significantly higher values were seen for all vascular indices in the basal zone. Reliability was greatest for the whole placental technique with intraclass correlation coefficients of 0.9 and limits of agreement for flow index (FI) of -3.81 to 2.50 (equivalent to -7.8% to 5.1%) compared with 0.6 and -13.2 to 18.3 (-64.6% to 78.2%) for the nontargeted sphere technique. Whole placental values are more reliable than biopsy techniques with significantly different results seen with each technique.


Asunto(s)
Angiografía/métodos , Imagenología Tridimensional/métodos , Placenta/irrigación sanguínea , Placenta/diagnóstico por imagen , Ultrasonografía Doppler/métodos , Ultrasonografía Prenatal/métodos , Adulto , Biopsia/métodos , Femenino , Humanos , Placenta/fisiología , Circulación Placentaria , Embarazo , Sensibilidad y Especificidad , Adulto Joven
4.
Ultrasound Med Biol ; 37(3): 376-85, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21256663

RESUMEN

Three-dimensional (3-D) power Doppler angiography (3-D-PDA) allows visualisation of Doppler signals within the placenta and their quantification is possible by the generation of vascular indices by the 4-D View software programme. This study aimed to investigate intra- and interobserver reproducibility of 3-D-PDA analysis of stored datasets at varying gestations with the ultimate goal being to develop a tool for predicting placental dysfunction. Women with an uncomplicated, viable singleton pregnancy were scanned at 12, 16 or 20 weeks gestational age groups. 3-D-PDA datasets acquired of the whole placenta were analysed using the VOCAL software processing tool. Each volume was analysed by three observers twice in the A plane. Intra- and interobserver reliability was assessed by intraclass correlation coefficients (ICCs) and Bland Altman plots. At each gestational age group, 20 low risk women were scanned resulting in 60 datasets in total. The ICC demonstrated a high level of measurement reliability at each gestation with intraobserver values >0.90 and interobserver values of >0.6 for the vascular indices. Bland Altman plots also showed high levels of agreement. Systematic bias was seen at 20 weeks in the vascular indices obtained by different observers. This study demonstrates that 3-D-PDA data can be measured reliably by different observers from stored datasets up to 18 weeks gestation. Measurements become less reliable as gestation advances with bias between observers evident at 20 weeks.


Asunto(s)
Algoritmos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Placenta/irrigación sanguínea , Placenta/diagnóstico por imagen , Ultrasonografía Doppler en Color/métodos , Adulto , Femenino , Humanos , Aumento de la Imagen/métodos , Variaciones Dependientes del Observador , Tamaño de los Órganos , Circulación Placentaria , Embarazo , Segundo Trimestre del Embarazo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
5.
Hum Reprod ; 22(12): 3116-23, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17947376

RESUMEN

BACKGROUND: The aim of this study was to quantify the three-dimensional (3D) ultrasound characteristics of ovaries in Caucasian women with polycystic ovarian syndrome (PCOS) and to examine if these values differed between different phenotypic forms. METHODS: 3D pelvic ultrasound was performed in 40 women with PCOS and in 40 controls. Total ovarian volume, stromal volume and echogenicity and antral follicle count (AFC) were measured and ovarian blood flow was quantified using both 3D power Doppler and two-dimensional pulsed-wave Doppler. RESULTS: Women with PCOS had a higher AFC (median 16.3 versus 5.5 per ovary, P < 0.001) and ovarian volume (12.56 versus 5.66 ml, P < 0.001). Stromal volume (10.79 versus 4.69 ml, P < 0.001) and stromal vascularization (VI: 3.85 versus 2.79%, P < 0.001; VFI: 1.27 versus 0.85, P < 0.001) were also increased in women with PCOS. There were no significant differences in stromal echogenicity or pulsed-wave Doppler indices between women with PCOS and the controls. Among the women with PCOS, ovarian vascularity was significantly higher in 30 women who were hirsute compared with normoandrogenic women (FI: 33.94 versus 29.30, P < 0.05) and in 14 women with PCOS who were of normal weight compared with obese women (VI: 4.51 versus 3.25%, P < 0.05; VFI: 1.56 versus 1.22, P < 0.05). CONCLUSIONS: Based on 3D ultrasound, women with PCOS have an increased stromal volume and vascularity. Stromal vascularity is significantly higher in women with PCOS who are hirsute and of normal weight.


Asunto(s)
Infertilidad Femenina/diagnóstico por imagen , Ovario/diagnóstico por imagen , Síndrome del Ovario Poliquístico/diagnóstico por imagen , Ultrasonografía Doppler/métodos , Adulto , Peso Corporal , Femenino , Humanos , Imagenología Tridimensional , Variaciones Dependientes del Observador , Ovario/irrigación sanguínea , Fenotipo , Estudios Prospectivos , Ultrasonografía Doppler/estadística & datos numéricos
6.
J Magn Reson Imaging ; 24(6): 1350-6, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17096391

RESUMEN

PURPOSE: To quantify T(1), T(2), and regional tissue perfusion in uterine tissues, with MR imaging in clinically feasible imaging times, using echo planar imaging (EPI) techniques over a single menstrual cycle. MATERIALS AND METHODS: A total of 24 healthy ovulating women were scanned; however, complete data sets through the menstrual cycle were not obtained from all women. Three scans were performed to coincide prospectively with the follicular, periovulatory, and luteal phases of the cycle. T(1) and perfusion were measured simultaneously using flow alternating inversion recovery (FAIR), while T(2) was measured using a single Hahn spin-echo (SE) EPI sequence. RESULTS: Between the follicular and periovulatory phases, statistically significant increases (P < 0.05) were seen for the T(2) of the endometrium and perfusion of the myometrium as well as the T(2)/T(1) ratio for both endometrium and myometrium. A statistically significant decrease was seen in the endometrial T(2) between the periovulatory and luteal phases of the cycle. Tissue differentiation was achieved using the parameters measured, with T(1) and T(2) being statistically greater for the endometrium than for the myometrium, and endometrial perfusion being statistically lower than myometrial perfusion. CONCLUSION: These results show the feasibility of using these techniques to measure T(1), T(2), and perfusion in uterine tissues and of extending this work to study pathological conditions.


Asunto(s)
Velocidad del Flujo Sanguíneo/fisiología , Imagen por Resonancia Magnética/métodos , Ciclo Menstrual/fisiología , Pelvis/anatomía & histología , Pelvis/irrigación sanguínea , Útero/irrigación sanguínea , Útero/fisiología , Adulto , Estudios de Factibilidad , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Perfusión/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
7.
Am J Obstet Gynecol ; 192(2): 648-54, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15696017

RESUMEN

OBJECTIVE: High-resolution magnetic resonance imaging (MRI) was used to monitor both uterine endometrial and junctional zone morphometry during the normal menstrual cycle. STUDY DESIGN: Twenty-four healthy, ovulating women were studied during a single menstrual cycle. Three scans were performed to prospectively coincide with the follicular, periovulatory, and luteal phases of the cycle. RESULTS: MRI data showed a significant increase in endometrial and junctional zone volume, between the follicular and periovulatory phases, with a significant decrease in endometrial volume observed from the periovulatory to luteal phases. The regularity index, which is a novel subjective assessment of junctional zone structure, varied significantly and demonstrated a less regular junctional zone in the luteal phase. CONCLUSION: This study has quantified the normal developmental changes of uterine tissue during the menstrual cycle with MRI. Junctional zone data from MRI may play a major role in future studies that investigate menstrual disorders, subfertility, and pathologic changes.


Asunto(s)
Ciclo Menstrual , Útero/anatomía & histología , Adulto , Endometrio/anatomía & histología , Endometrio/diagnóstico por imagen , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Ultrasonografía
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